Railway traffic controlling apparatus



RAILWAY TRAFFIC CONTROLLING APPARATU-S Filed Oct. 22, 1941v 45' 2 p 36 26011.13 C' i d @lf-@121 Patented Oct. `13, 1942 UNHTED STATES RAILWAY TRAFFIC CONTROLLING APPARATUS John M. Pelikan, Chicago, Jil., assignor to The Union Switch and Signal-Company, Swissvale, Pa., a corporation of Pennsylvania Application October 22, 194.1, Serial No. 416,007

4 Claims.

My invention relates to railway trafc controlling apparatus, and it has particular reference to the organization of such apparatus into railway trafc controlling systems for controlling the operation of railway track switches and signals governing traic over such switches.

Interlocking systems heretofore proposed for controlling the operation of railway track `switches and signals governing trailic over such switches, usually incorporate approach locking Imeans rendered effective upon the approach of va train, to permit alteration of a route established for such train at the expiration of a predeter- Amined time delay. Such a time delay ordinarily is enforced through the medium of a time release device having contacts which open and Yclose at the end of one or more predetermined time intervals, and such systems have been arranged so as to insure against a reduction in the release period of the approach locking, should the contacts of the time release device fail to return to their normal positions after an operation of the device. One such system of this type is shown,

lfor example, in United States Letters Patent No.

2,198,712 granted April 30, 1940, tol-I. C. Vantassell for Railway traffic controlling apparatus.

Insuch systems, it often happens that slow speed or call-on signals are employed to authorize a train to enter a section under reduced speed when conditions in advance are such that the high speed signal normally governing such movement is in its stop position. Where call-on signals are employedin addition to the usual high .speed signals, it is advantageous to provide means for` effecting release of the approach locking at the end of either a short or a long time release interval according as the call-on signal or high- -speed signal is cleared. This arrangement avoids portant considerations, it is an object of mylinvention to provide an interlocking system for controlling track switches and -signals and incorporating novel and improved means for releasing the approach locking at the end of one or another of two differentr time release intervals.

AAnother object of my inventionis to. prov-ide -an interlocking system of the type` described and incorporating means for releasing the approach locking at the end of a relatively short time interval when a low speed signal is cleared and at VVAthe end of -a relatively longer time interval when a highspeed signal is cleared.

A further object Ais to provide means, in a system of the type shown inthe aforesaid `Vantassell Patent-No. 2,198,712, for effecting different time releases of approach locking according as ahigh speed or a low speed signalis cleared.

-The above-mentioned and other important objects and characteristic features of my invention which will become readily apparent from the following description, are attained in accordance with my linvention by incorporating into a system of the type vshown in VantassellPatentfNo.

2,198,712, circuit means controlled by a call-on Asignal control relay or a diverging route relay, for

effecting a time release of the approach/locking at the end of a time interval shorter than that enforced when a high speed signal is cleared and then put to stop.

-I shall describe one form of apparatus embodying my invention,.and shall then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic YView illustrating one form of apparatus embodying my invention.

Referring to the drawing, the `diagram at the top represents a stretch of railway` track X provided with a track section IT including a track `switch W for connecting a diverging or auxiliary track Y to track X. Section IT is provided with a normally closed circuit track circuit including a Ynormally energized track `relay ITR. as indi- Vcated conventionally ,in the drawing. Switch W -is operatively associated with a power operated switch mechanism SM controlled through the medium of` a polarized relay WR. It is deemed ysufficient to state that vmechanism SM is renldered effective to operate switch W only when `front contact 5 of relay WR is closed, and that theswitch mechanism is conditioned to operate switch W to its normal position, as shown, or to its reverse position according as polar contact member 6 of relay WR, as viewed in the drawing,

.is Ainlits left-hand or its right-hand position, re-

spectively. Switch .W alsohas operatively associated therewith a `.movable contact member'l which is operatedinto engagement with contact B when ythe switch is set for a high speed .movement .on track-X and -is operated into engagement with contact 9 when the switch is set for adivergingmovement from .track-XC ontothe diverging track Y. A normal switch repeater relay INWP is energized over a circuit which includes contact '1 '8 of switch W, and a reverse switch repeater relay IRWP is energized over a circuit completed when contact 1 9 of switch W is closed. Relay I NWP or IRWP when energized indicates that switch W occupies its normal or its reverse position, respectively.

The movement of traic on the main track over switch W is governed by a signal, designated by the reference character 2, comprising a high speed unit a and a low speed unit c. Unit a of signal 2 normally indicates stop but may be cleared, when a signal control relay 2AI-IR is picked up, to permit a high speed movement over the switch on the main track when conditions are favorable for such movement. This unit may be of any suitable type, such as color light, position light, searchlight, etc., and is provided with a circuit controlling contact I which engages a iixed contact II when and only when unit a indicates stop.

Unit c of signal 2 normally indicates stop but may be cleared by causing a signal control relay ZCHR to pick up when switch W is set for a diverging movement, or when a call-on signal control relay, designated by the reference character ZCOS, is energized. Unit c has operatively associated therewith a contact member I2 which is arranged to engage a xed contact member I3 when and only when the unit indicates stop.

An approach locking relay, designated by the reference character ZAS, controls, in part, the switch control relay WR in such manner that relay WR can be energized when and only when relay 2AS is picked up to close its front contact I5.

A signal repeater relay 2RP, normally energized over a stick circuit including its own front contact I6 and completed when signal units a and c indicate stop and contacts Ill-II and I2-l3 are closed, cooperates with an approach relay 2AR, track relay ITR, call-on control relay 2COS, and with time element means, hereinafter referred to, in the control of the approach locking relay EAS. The approach relay 2AR is arranged to be controlled in any suitable manner, not shown, so as to be released when a train approaches section IT on track X while moving from left to right as viewed in the drawing.

The time element means comprise a time element device ZTE and a stick relay ZTES. Device ZTE operates a first contact I8 which is normally open and which is slow to close when the device is energized. Device 2TE also operates a second contact I9 which is normally closed, and which opens in response to energization of device ZTE and is slow to close when the device becomes deenergized.

In order to simplify the drawing, relay contacts have been represented at times remote from the relays which cause such contacts to operate, but in such cases each contact bears a reference character relating not only to the respective relay operating such contact but also a number individual to each of such contacts. For example, the reference character ZAS has been placed immediately above contact I to indicate that this contact is operated by relay ZAS, and this contact has been represented closed to indicate that relay ZAS is normally picked up.

The apparatus embodying my invention is in its normal condition, as represented in the drawing, when approach relay ZAR is picked up, section IT is unoccupied and units a and c of signal 2 indicate stop, respectively. In this condition of the apparatus, relay 2RP is energized over two alternate circuit paths, a rst or pick-up circuit of which extends from one terminal B of a suitable source of current, such as a battery not shown but having its opposite terminals designated by the reference characters B and C, through contact Ill- H operated by unit a of signal 2, back point of contact 20 of relay ZI'ES, back point of contact I9 of time element device ZTE, back point of contact 2| of relay ZTES, the winding of relay 2RP and contact I3-I2 operated by unit c of signal 2 to terminal C. The second or stick circuit path in the energizing circuit of relay 2RP includes its own front contact It connected around back points of contacts 20 and 2| of relay 2TES and back point of contact I 9 of time element device 2TE. Relay 2AS is energized over a circuit extending from terminal B through front contact 22 of relay 2RP, front contact 23 of approach relay 2AR, and the winding of relay ZAS to terminal C, and relay 2AS is provided with an alternate stick circuit path which includes its own front contact 24 connected in the just traced circuit around front contact 23 of relay ZAR. Relay WR is energized over a circuit, a portion of which is represented including front contact I5 of relay 2AS. The remainder of the circuit of relay WR, not shown, may be controlled in any suitable manner, such for example as by a lever operated by a leverman in an interlocking tower. Relays ITR and ZAR also are energized.

Under the above assumed conditions, the operator may clear unit a of signal 2 by moving a signal lever 2V from its normal position N to its reverse position R. Lever 2V is provided with contacts each bearing a reference character N or R to indicate that such contact is closed in the normal (N) or reverse (R) position of the lever, respectively. When lever 2V is operated to its reverse position, relay ZAI-IR is caused to become picked up over a circuit extending from terminal B through contact 26 of lever 2V, closed in the reverse position of the lever, front contact 21 of relay ITR, front contact 28 of normal switch repeater relay INWP, and the Winding of relay ZAHR to terminal C. Relay 2AHR when picked up causes unit a of signal 2 to clear over circuit means not shown but indicated conventionally in the drawing. When unit a clears, contact Ill-II opens to cause relay 2RP to release, and relay 2RP opens its front contact 2"'2 in turn to cause relay 2AS to release. Contacts I6 and 2d of relays 2RP and ZAS, respectively, open to open the stick circuit paths in the energizing circuits of the respective relays.

Under the assumed conditions, if a train approaches section IT and causes approach relay ZAR to release, the approach locking is imposed upon the system. This is effected due to the fact that if, at this time, the leverman restores lever 2V to its normal position, relay ZAHR releases, unit a goes to stop, and contact Ill-II closes to cause relay 2RP to become energized over its previously traced pick-up circuit, which circuit includes normally closed contact I9 of time element device ZTE and hence provides a check that the contacts of device 2TE are in their normal positions. Front contact 22 of relay 2RP accordingly closes, but with both front contacts 23 and 24 of relays ZAR and 2AS open, relay 2AS remains in its released position for a relatively long time interval imposed by time element device ZTE, which device becomes energized over a circuit extending 'from terminal through front contact 22 of relay ZRP, back point of contact 2'4 oi relay `2AS, back point of contact 30 of rel'ay 2TES, and the winding of relay 2TE to terminal C. At the end of a first predetermined time interval, contact I8 of relay '2TE closes to complete an obvious circuit for relay ZTES, which relay picksup to operate its contacts 20, '2| and 30 from their back to theirfront points. An

obvious stick circuit for relay ZTES is now corn'v pleted at the front point of contact 3U of relay 2TES, which stick circuit holds that relay energized when contact I8 of device 2TE` opens due to its energizing circuit being opened at the back point of contact 30 of relay ZTES. At the end of a second predetermined time interval, contact I9 of device 2TE closes and relay ZAS becomes energized over a circuit extending from terminal B through front Contact 22 of relay ZRP, front point of contact 2E! of relay ZTES, back point of contact I9 `of device 2TE, front point of Vcontact EI of relay and the winding of relay 2AS to terminal C. Relay EAS operates its contact 2:3 from its back point to deenergize stick relay ETES, and contact 2d engages its front point to complete the stick circuit for relay ZAS, which circuit holds that relay energized after relay 2TES releases its contacts 2c and 2| at the end of its slow release interval. Front contact I of relay HAS, interposed in the control circuit of relay WR, is now closed and it follows that the apparatus is eiiective to require a predetermined time interval to expire before control of switch W can be eiiected if a high speed signal is cleared and then :set to stop when approach relay ZAR is released.

If, however, unit a is cleared and the train accepts the signal and enters section IT, then the approach locking is caused to be immediately released, in the following manner: relay ZAHR releases due to the opening of contact 2'I of relay ITB, and unit a goes to stop to close contactit-ii and cause relay ERP to become energized over its previously traced pick-up circuit. Relay am? of course picks up to close its front conta-ct 22, and relay ZAS accordingly becomes energized over what I shall term a track circuit release circuit which extends from terminal B through front contact 22 of relay ZRP, back contact 32 of track relay QTR, back contact 33 of call-on control relay 2COS, and the winding of relay AS to terminal C. It is to be noted that this circuit includes a back Contact 33 of relay ECOS, and that this circuit is effective to release the approach locking whenever a train accepts a high speed signal aspect and enters section IT.

In the event that switch W is in its normal position but conditions are such that high speed unit a of signal 2 displays stop, unit c of signal 2 may be cleared by the leverfinan reversing signal lever 2V and closing push button 'COPB. When this happens, relay QCOS picks up over a pickup circuit extending from terminal B through contact 35 of push button ECCPB, contact 36 of lever 2V, closed in the reverse position of the lever, front contact :il of relay 2R? and the winding of relay ?COS to terminal C. Relay ZCOS, when picked up, closes its front contact 38 to complete a circuit extending from terminal B through contact 26 of lever 2V, closed in the reverse positien of the lever, front contact 3B of relay ZCOS and the winding of relay `ZCHR to terminal C, whereupon relay ECE-IR picks up and causes unit c of `signal 2 to clear over a circuit including front contact 39 of relay 2CHR and contact 40 of lever 2V, which contact is closed in the reverse position of the lever. Contact I2--I3 accordingly opens, relay ZRP releases, and relay 2AS `in turn releases to close its back Contact 24 and thereby complete an obvious stick circuit for relay ZCOS, which circuit'extends from terminal B through back contact 4I of relay ZAS, front contact 42 `of relay ZCOS, and the winding of relay 2COS to terminal C. The leverman may now release push button ZCOPB.

If, now, approach relay ZAR is released by a vtrain approaching section IT, the apparatus is arranged to permit an operation of switch W at the 'end of a time release period shorter in duration than that enforced when a high speed signal is cleared and then put to stop. For example, if with the apparatus in the condition just described, the leverrnan restores lever 2V to its normal position, contact 4e of lever 2V opens and unit c accordingly goes to stop to close its Contact 12-53 and cause repeater relay ZRP to become energized over its previously traced pick-up circuit including back points of contacts Zit and 2| of relay ZTES and back point of contact I9 of device ZTE. Relay 2R? picks up to the close its front contact 22 and thereby energize time element device ETE over a circuit previously traced, and at the end of a predetermined time interval, contact I8 of device. 2TE closes to energize relay ETES. When this. happens, Contact 33 of relay ETES operates away from its back point to deenergize device 2TE,. and this contact engages its front point to complete the previously mentioned stick circuit of relayA ETES. Contacts 2o and tI of relay ZTES. also operate to their front points, whereuponv relays EAS is energized over a circuit extending from terminal B through front Contact 22 of.' relay ERP, front point or" contact 23 of relay ETES, front contact de of relay RCCS, front contact 45 of relay ERP, front point of contact 2I of relay ETES, and the winding of relay EAS to terminal C. It is to he noted that the circuit just traced includes front Contact is of relay ECOS and front contact i5 of relay 2R?, which contacts provide an alternate path around contact I9 of time element device ETE interposed in the previously traced circuit over which relay 2AS is released at the end of the predetermined time interval imposed when a high speed signal is cleared and lever 2V is restored to normal. Thus, the time interval imposed when .a low speed signal is cleared and then set to stop is determined only by the time required for contact I3 of device ETE to close, and does not irlclude the time required for the other Contact I9 of device ETE to be restored to its normal position. It follows, therefore, that when a low speed signal is cleared and then set to stop, the approach locking is released at the end of a time interval considerably shorter than that irnposed when a high speed signal is cleared and then restored to its stop indication.

The apparatus further is arranged so that when unit c is cleared for a diverging route, the shorter time interval is imposed on the release of the approach locking. For example, if switch W is in its reverse position, relay IRWP is then energized, and iront contact of this relay is then connected, in series with iront contact 45 of relay ZRP, around contact i9 of device ZTE in the previously traced circuit over which relay 2AS is energized at the end of the long time release interval. It follows, therefore, that when unit c is cleared and then set to stop with switch W in its reverse position, the alternate path formed by contacts 4G and 45 of relays IRWP and ZRP, respectively, enables relay 2AS to become energized at the end of the time required for contact I8 of device ETE to close, and such time interval does not include the time required for contact I9 of device ZTE to close.

The apparatus is additionally arranged so that when unit c is cleared as a call-on signal, track circuit release of approach locking cannot be effected. For example, assume that call-on relay ZCOS is picked up, and unit c of signal 2 is cleared. When the train accepts this indication and enters section IT, relay I'IRl releases, but with back contact 33 of relay ZCOS now open, the previously traced circuit, over which track circuit release of the approach locking is effected when a train accepts a high speed signal and enters section IT, accordingly cannot be completed. In such an event, the approach locking is released only at the end of the short time release interval, i. e. the interval required for device ETE to close its contact I8. If, however, unit c is cleared for a diverging route and relay ECOS is released, then when the train enters section IT, relay I TR closes its back contact 32 and completes through back contact 33 of relay ZCOS the previously traced track circuit release circuit for relay ZAS, whereupon relay 2AS picks up to release immediately the approach locking.

From the foregoing description, it is readily apparent that I have provided an interlocking system for controlling railway switches and signals governing trailic over such switches, and have incorporated therein novel and improved means for effecting the release of approach locking in such a system at the end of a relatively short or a relatively long time interval according as a slow speed signal is cleared and then set to stop, or a high speed signal is cleared and then set to stop. In addition, the apparatus is arranged to provide a track circuit release for the approach locking when the high speed signal, or a low speed diverging route signal, is accepted by a train, but such track circuit release is not eiected when the low speed signal employed as a call-on indication is accepted by a train.

Although I have herein shown and described only one form of railway traffic controlling apparatus embodying my invention, it is understood that various changes and modications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In a railway interlocking system of the class comprising, a railway track switch, a signal indicating proceed, slow speed, or stop, for governing traflic over said switch, an approach locking relay normally energized over a stick circuit completed when said signal is at stop and which relay when deenergized prevents operation of the switch, a time element device having a rst time contact which is slow to close when said device is energized and having a second time contact which opens upon energization of said device and which is slow to close when said device becomes deenergized, a stick relay .provided with a pick-up circuit including said rst time Contact of said time element device, an energizing circuit for said time element device corn- 75 pleted when said signal is at stop and including a back Contact of said locking relay and a back point of a contact of said stick relay, a stick circuit for said stick relay including a front point of said contact of said stick relay, and a rst pick-up circuit for said approach locking relay completed when said lsignal is at stop and including said second time contact of said time element device and a front point of a second contact of said stick relay; the combination with the foregoing apparatus of, a signal control relay eiective when energized for causing said signal to indicate call-on, manually operable means for energizing said signal control relay, and an auxiliary pick-up circuit for said approach locking relay, said circuit including a front contact of said signal control relay and said front point of said other contact of said stick relay.

2. In a railway interlocking system ol the class comprising, a railway track switch, a signal indicating proceed, slow speed, or stop, for governing traffic over said switch, an approach locking relay normally energized over a stick circuit completed when said signal is at stop and which relay when deenergized prevents operation of the switch, a time element device having a first time contact which is slow to close when said device is energized and having a second time Contact which opens upon energization of said device and which is slow to close when said device becomes deenergized, a stick relay provided with a pick-up circuit including said iirst time contact of said time element device, an energizing circuit for said time element device completed when said signal is at stop and including a back contact of said locking relay and a back point of a contact of said stick relay, a stick circuit for said stick relay including a front point of said contact of said stick relay, and a first pick-up circuit for said approach locking relay completed when said signal is at stop and including said second time contact of said time element device and a front point of a second contact of said stick relay; the combination with the foregoing apparatus of, a switch repeater relay energized only when said switch is set for a slow speed movement, and an auxiliary pick-up circuit for said approach locking relay, said circuit including a front contact of said switch repeater relay and said front point of said other contact of said stick relay.

3. In a railway interlocking system of the class comprising, a railway track switch, a signal indicating proceed, slow Speed, or stop, for governing traffic over said switch, an approach locking relay normally energized over a stick circuit completed when said signal is at stop and which relay when deenergized prevents operation of the switch, a time element device having a irst time contact which is slow to close when said device is energized and having a second time contact which opens upon energization of said device and which is slow to close when said device becomes deenergized, a stick relay provided with a pick-up circuit including said iirst time contact of said time element device, an energizing circuit for said time element device completed when said signal is at stop and including a back contact of said locking relay and a back point of a contact of said stick relay, a stick circuit for said stick relay including a front point of said contact of said stick relay, and a iirst pick-up circuit for said approach locking relay completed when said signal is at stop and including said second time contact of said time element device and a front point of a second contact of said stick relay; the

combination with the foregoing apparatus of, a signal control relay effective when energized for causing said signal to indicate call-on, manually operable means for energizing said signal control relay, a switch repeater relay energized only when said switch is set for a slow speed movement, and an auxiliary pick-up circuit for said approach locking relay, said circuit being conditioned to be completed whenever either said switch repeater relay or said signal control relay is energized.

4. In a railway interlocking` system of the class comprising, a railway track switch, a relay responsive to traiiic adjacent said switch, a signal indicating proceed, slow speed, or stop, for governing trac over said switch, an approach locking relay normally energized over a stick circuit completed when said signal is at stop and which relay when deenergized prevents operation of the switch, a time element device having a rst time contact which is slow to close when said device is energized and having a second time contact which opens upon energization of said device and which is slow to close when said device becomes deenergized, a stick relay provided with a pick-up circuit including said rst time contact of said time element device, an energizing circuit for said time element device completed when said signal is at stop and including a back contact of said locking relay and a back point of a contact of said stick relay, a stick circuit for said stick relay including a front point of said contact of said stick relay, and a first pick-up circuit for said approach locking relay completed when said signal is at stop and including said second time contact of said time element device and a front point of a second contact of said stick relay; the combination with the foregoing apparatus of, a signal control relay eiective when energized for causing said signal to indicate call-on, manually operable means for energizing said signal control relay, an auxiliary pick-up circuit for said approach locking relay, said circuit inciuding a front contact of said signal control relay and said front point of said other contact of said stick relay, and another auxiliary pick-up circuit for said approach locking relay, said other circuit including a back contact of said traic responsive relay and a back contact of said signal control relay.

JOHN M. PELIKAN. 

